The present invention relates in general to mechanical structures such as capsules, pellets, ball bearings and the like, and in particular to diamond capsules and methods of manufacture.
Ball bearings are usually made of metal or ceramic materials that can be finished to a surface smoothness with deviations on the order of a few nanometers (nm). Standard methods for making ball bearings include using a stamping machine to cut a ball from a wire of metal or ceramic material, then rolling the ball between plates to smooth over the rough edges left from the stamping procedure.
For other applications, hollow capsules are made from glass microballoons or from hollow cylindrical wires, in much the same fashion as ball bearings. Surface roughness or smoothness is imposed by laser ablation. Surface deviations are typically on the order of many nanometers, and deviations from spherical shape are on the order of a hundred nanometers to a micron.
Capsules are also sometimes made by manufacturing sections (e.g., hemispherical shell sections), then joining or welding the sections together at their peripheral edges. Conventional machining techniques are then used to bring the surface to the requisite shape and smoothness.
Current technology does not provide materials or processes capable of shaping and smoothing ball bearings or capsules to sub-nanometer precision. In addition, current materials are not suited for use at extreme temperatures (e.g. near absolute zero and/or above 100 K), or where extreme demands are placed on the strength and uniformity of the ball bearing or capsule. In addition, current methods for making ball bearings, capsules and similar structures generally do not provide the ability to form complex structures or to incorporate specific electromagnetic properties into the capsule.
It would therefore be desirable to provide improved materials and methods for manufacturing ball bearings, capsules, and similar structures.